Quality-adjusted time without symptoms or toxicity analysis of nivolumab plus chemotherapy versus chemotherapy alone for the management of previously untreated patients with advanced gastric cancer, gastroesophageal junction cancer, or esophageal adenocarcinoma

BACKGROUND: The phase 3 CheckMate 649 established superior overall survival of nivolumab in combination with chemotherapy (NIVO + chemo) compared with chemotherapy (chemo) alone as a first-line treatment for patients with Her2-negative advanced gastric cancer, gastroesophageal junction cancer, and esophageal adenocarcinoma (GC/GEJC/EAC). This post hoc trial analysis aimed to evaluate the benefit of NIVO + chemo using quality-adjusted time without symptoms or toxicity (Q-TWiST) to further account for quality of life (QoL) in different health states depending on disease progression and treatment toxicity. METHODS: Using data from CheckMate 649, we evaluated the quality-adjusted survival gain associated with NIVO + chemo compared with chemo alone among all randomized patients and repeated similar analyses among those with programmed cell death-ligand 1 (PD-L1) combined positive score (CPS) ≥ 5. Relative Q-TWiST gains of ≥ 10% were predefined as clinically important. RESULTS: In all randomized patients, those receiving NIVO + chemo had a mean Q-TWiST gain of 1.8 (95% CI 0.9, 2.7) months compared with those receiving chemo alone. The relative Q-TWiST gain was estimated to be 12.8%. Patients with PD-L1 CPS ≥ 5 had greater quality-adjusted survival gain from NIVO + chemo with an estimated Q-TWiST gain of 2.8 (95% CI 1.5, 4.1) months, representing a relative gain of 20.6%. Subgroup analyses and sensitivity analyses with various QoL utility values yielded consistent findings in favor of NIVO + chemo compared with chemo alone. Q-TWiST gain from NIVO + chemo increased with longer duration of follow-up. CONCLUSIONS: NIVO + chemo was associated with a statistically significant and clinically important gain in quality-adjusted survival compared with chemo alone among previously untreated patients with advanced GC/GEJC/EAC.